Status and Conservation of Coral Reefs in Costa Rica
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Status and conservation of coral reefs in Costa Rica Jorge Cortés1, 2, Carlos E. Jiménez1, Ana C. Fonseca1, 3 & Juan José Alvarado1 1. Centro de Investigación en Ciencias del Mar y Limnología (CIMAR), Ciudad de la Investigación, Universidad de Costa Rica, San Pedro, 11501-2060 San José, Costa Rica; [email protected] 2. Escuela de Biología, Universidad de Costa Rica, San Pedro, San José, Costa Rica. 3. World Wildlife Fund (WWF), San José, Costa Rica, Interlink #718, P.O. Box 02-5635, Miami, Florida 33102, USA. Received 30-VIII-2009. Corrected 03-X-2009. Accepted 12-XII-2009. Abstract: Costa Rica has coral communities and reefs on the Caribbean coast and on the Pacific along the coast and off-shore islands. The Southern section of the Caribbean coast has fringing and patch reefs, carbonate banks, and an incipient algal ridge. The Pacific coast has coral communities, reefs and isolated coral colonies. Coral reefs have been seriously impacted in the last 30 years, mainly by sediments (Caribbean coast and some Pacific reefs) and by El Niño warming events (both coasts). Monitoring is being carried out at three sites on each coast. Both coasts suffered significant reductions in live coral cover in the 1980’s, but coral cover is now increasing in most sites. The government of Costa Rica is aware of the importance of coral reefs and marine environments in general, and in recent years decrees have been implemented (or are in the process of approval) to protect them, but limited resources endanger their proper management and conservation, including proper outreach to reef users and the general public. Rev. Biol. Trop. 58 (Suppl. 1): 33-50. Epub 2010 May 01. Key words: coral reefs, Costa Rica, monitoring, GCRMN, conservation, management. Costa Rica has coral reefs on the Carib- coast of Costa Rica is oriented toward the reefs, bean coast and on the Pacific side (coast as are also the fisheries. and off-shore islands). The Caribbean coast is The Pacific coast of Costa Rica is 1 160km 212km long and consists mainly of high-energy long, and has a high diversity of habitats: rocky sandy beaches that on the Southern section are shores of a wide variety of rock types, sandy interrupted by carbonate promontories (Fig. 1). beaches of several compositions and grain These promontories are made up primarily of size, mangrove forests, estuaries, a tropical fossil reefs (Pleistocene, Holocene), and beach- fjord, islands of various sizes, and several gulfs rock in some sections. Extant reefs develop on and bays (Fig. 2). The northern section of the top of these rocky outcrops (Cortés & Guzman coast (Gulf of Papagayo) is characterized by 1985, Cortés & Jiménez 2003a). Three coral reef a dry tropical forest, with a very dry season areas are recognized on the Caribbean coast: from December to April, and a rainy season 1) fringing reefs between Moín and Limón, 2) from May to November. This part of the coast fringing and patch reefs, and carbonate banks at is exposed to seasonal upwelling (McCreary Cahuita National Park, and 3) fringing and patch et al. 1989) during the dry season due to the reefs, carbonate banks, and incipient algal ridge crossing the isthmus of Trade Winds. The cen- between Puerto Viejo and Punta Mona (Fig. 1). tral and southern coast is covered with tropical Seasonal variability is minimum along this coast, rain forest, with a transition zone in between in with rains year round and no upwelling. Most of the Central Pacific coast. Coral communities, the touristic activity on the Southern Caribbean reefs and isolated coral colonies can be found Rev. Biol. Trop. (Int. J. Trop. Biol. ISSN-0034-7744) Vol. 58 (Suppl. 1): 33-50, May 2010 33 Fig. 1. Caribbean coast of Costa Rica, monitoring sites and Marine Protected Areas. Codes: PNC=Parque Nacional Cahuita; REGAMA=Refugio Nacional de Vida Silvestre Gandoca-Manzanillo. along the Pacific of Costa Rica, which has been coast which is subject to heavy wave action, divided into eight regions (Cortés & Jiménez with the largest reefs growing on the leeward 2003b): 1) Santa Elena, in the Northern section side of the islands. This area is exposed to of the coast next to the border with Nicaragua; freshwater runoff, sewage, petroleum pollu- 2) Bahía Culebra, to the South of Santa Elena tion and solid wastes from the main ports on and North of Península de Nicoya; 3) Península the Caribbean (Mata et al. 1987, Guzman & de Nicoya, mainly the seaward side of the pen- Jiménez 1992, Guzman & García 2002, Acu- insula, since the inner section is an estuarine ña-González et al. 2004). The coast between environment with very little coral growth; 4) Moín and the Port of Limón is bordered by a Pacífico Central, extends from the East end of carbonate platform that extends from above the Golfo de Nicoya to the largest mangrove area upper tidal zone down to 15m depth (Cortés of Costa Rica, the Sierpe-Térraba complex; 5) & Guzman 1985). The submerged platform Península de Osa, the outer section and part of is covered with algae, hydroids, sponges and the entrance to Golfo Dulce; 6) Golfo Dulce, isolated corals. The most abundant corals in includes the reefs within the gulf; and offshore 1983, when the area was surveyed, were: P. islands: 7) Isla del Caño, 15km from the coast, astreoides and A. agaricites forma purpurea and 8) Isla del Coco, more than 500km from (Cortés & Guzman 1985). Beyond 15m depth the coast (Fig. 2). the bottom consisted of soft mud (Cortés 1998). Isla Uvita is off the Port of Limón (Fig. 1), but STATUS OF THE CORAL REEF BENTHOS a strong current separates it from the port and CARIBBEAN its pollution. So, it is possible to observe well- developed reefs around the island. The east Moín-Limón: Fringing reefs and carbon- side had an extensive carbonate platform, with ate platforms are found in this section of the microatolls of Siderastrea siderea in the lagoon 34 Rev. Biol. Trop. (Int. J. Trop. Biol. ISSN-0034-7744) Vol. 58 (Suppl. 1): 33-50, May 2010 Fig. 2. Pacific coast of Costa Rica, monitoring sites and Marine Protected Areas. Codes: ACG= Área de Conservación Guanacaste; ACM Isla del Coco= Área de Conservación Marina Isla del Coco; ACOPAC= Área de Conservación Pacífico Central; ACOSA= Área de Conservación de Osa; ACT= Área de Conservación Tempisque; PNC= Parque Nacional Corcovado; PNMA= Parque Nacional Manuel Antonio; PNMB= Parque Nacional Marino Ballena; PNSR= Parque Nacional Santa Rosa; RACB= Reserva Absoluta Cabo Blanco; RB Isla del Caño= Reserva Biológica Isla del Caño. that was further exposed with the 1991 Limón & Risk 1984, 1985, Cortés & Guzman 1985). Earthquake (Cortés et al. 1992). A monitoring Partch reefs are found within the lagoon and car- station was established in 2005 in the west side, bonate banks off shore. The coral reef at Cahuita coral cover was very low and sponges were had been degrading during the last 30 years due dominant (Fonseca et al. 2006a). to siltation, other anthropogenic impacts and natural causes (some of them exacerbated by Cahuita: The largest fringing reef of the human activity): massive death of organisms, Caribbean in the country is located at Parque earthquake, and warming events. Live coral cov- Nacional Cahuita (Fig. 1). This reef consists of erage decreased from 40% in the early 1980’s to three barriers; the outer barrier, stretching for 10% in the early 1990’s (Cortés 1994). Using 5km from the Western side of Punta Cahuita, to the AGRRA surveying protocol, live coral was the Eastern side, it is separated from the coast 2-3% in the late 1990’s (Fonseca 2003). The between 100m and 2km. Between this barrier reef of Cahuita has been monitored since 1999 and the coast there is a small fringing reef, about using the CARICOMP monitoring protocol, and 500m long and within 100m from the shore, in recent years with funding from the South- called the inner crest. Finally, a 100m barrier is ern Tropical America-Global Coral Reef Moni- located of the Western end of the reef (Cortés toring Network (STA-GCRMN) node. At the Rev. Biol. Trop. (Int. J. Trop. Biol. ISSN-0034-7744) Vol. 58 (Suppl. 1): 33-50, May 2010 35 CARICOMP site, live coral increased slightly coral extraction for curio-trade, sewage and solid from around 15% to 17% in 2004, however turf wastes. The reef at Punta Cocles (Fig. 1) had algal cover has increased significantly (Fonseca 5% live coral cover in 1983, with S. siderea as et al. 2006a, Fig. 3). the dominant species (Cortés & Guzman 1985); The populations of the black sea urchin, in 1988 live coral cover was 12.7±5% while Diadema antillarum, which were decimated in 1995 it was 13.2±3.6% (Jiménez & Cortés in the early 1980’s in Costa Rica and wider unpbl. data). Live coral cover has continued to Caribbean (Lessios et al. 1984, Murillo & increase and by 2002 it was 16% (Fernández & Cortés 1984) are recovering. Before the 1983 Alvarado 2004). This increase was probably due mass mortality densities were 3.6 to 8.8 ind/m2 to the natural and anthropogenic protection of (Valdez & Villalobos 1978), after the mortality the reef; it is located far from any large sediment densities were 0.25 to 2 ind/m2. By 1992 it had source or rivers and the local people close to the reached 0.001 ind/m2 (Cortés 1994) and in 2004, reef protect it because they consider it as part 0.3 to 0.7 ind/m2 (Alvarado et al. 2004, Fonseca of their homes (Fernández & Alvarado 2004). et al.